More than 5,000 civilians killed in Iraq this year, says U.N.

At least 5,576 Iraqi civilians have been killed this year in violence, the United Nations said on Friday in the most detailed account yet of the impact of months of unrest culminating in an assault by Sunni militants through the north of the country, Reuters reported.

At least 11,665 have been wounded since January, when Sunni insurgents led by al Qaeda offshoot now known as the Islamic State overran the city of Falluja in the western province of Anbar, the U.N. said in a report.

Last month, the insurgents seized swathes of northern Iraq, including the area's largest city Mosul. Of the 2,400 people killed in June, 1,531 were civilians, the U.N. said earlier this month.

The report documents what it calls "systematic and egregious violations" of international law by the group now calling itself the Islamic State.

The U.N found the group had executed civilians, committed sexual violence against women and girls, carried out kidnappings and targeted assassinations of political, community, and religious leaders and killed children, among other violations.

The report also details violations committed by government forces and affiliated groups, citing "summary executions/extrajudicial killings of prisoners and detainees", which it said may constitute a war crime.

The U.N. noted that the "deteriorating security situation" had limited its ability to directly monitor and verify incidents.

More than 1.2 million people had been displaced since violence escalated last month, according to the report.